2013 Volume 7 Issue 4 Pages 528-538
Extra low-power magnetic suspension system is achieved using solely solar power. Presently, solar cells have become more efficient and cost-saving year by year. In this work, a solar power generation technique is combined with zero-power control magnetic suspension. The zero-power control is achieved by converging the control current to zero in the steady states where the bias force generated by a permanent magnet is balanced with the gravitational force. Therefore, the steady-states power consumption becomes virtually zero in this suspension system. However, peripheral devices including sensors and controllers need power in both transient and steady states. Hence, the power consumed in the peripheral devices becomes dominant. In this work, dedicated power-saving peripheral devices are fabricated. It is observed that the average power consumed by the electromagnet is 20[mW] for suspending a 90-gram mass, and the power consumed by the peripheral devices is 13[mW]. In contrast, a conventional system consumes a few watts to suspend a floator of the same dimensions. The solar cells used in the apparatus has a maximum power capacity of 2[W] under a typical summer sunlight (approximately 120[klx]). The fabricated system can achieve stable suspension even under a illuminance of a fluorescent lamp of 5[klx].
